Managing Outbreaks: Is Culling The Only Solution?

In the last few days, two East Asian countries – Japan and South Korea – have seen sudden, rapid outbreaks of bird flu (H5N1) and foot and mouth disease (FMD) respectively. The FMD outbreak was first reported in South Korea last week, with some reports claiming that this epidemic could cost South Korea USD1.4 billion in losses from exports, vaccinations, culling and compensation for farmers. Meanwhile, Japan was alerted to new cases of H5N1 in its southwest on 22 January after six chickens found dead at a farm in Miyazaki were tested and found to have died from the virus.

Although FMD and H5N1 are very different diseases, there is a significant common thread in both the Japanese and South Korean outbreaks: both countries have attempted to halt the disease outbreaks by culling a large percentage of their livestock population.

To combat the current H5N1 outbreak, Japan culled 410,000 chickens in Miyazaki in addition to 20,000 chickens in Shimane, where there was a minor H5N1 outbreak last November. This is not, by far, the first time Japan has practiced mass culling in the event of an outbreak: Japan culled about 288,000 pigs, cows and cattle in Miyazaki last year to contain the nation’s first outbreak of foot-and-mouth disease since 2000. Alongside, South Korea’s government has called for the mass culling of animals (pigs and cows because of FMD, chickens and ducks because of H5N1, as well as smaller numbers of other animals like goats) on a large scale. Reports estimate that over a million pigs have been slaughtered and the total number of all animals killed ranges in the millions.

The World Health Organization (WHO) recognises that culling has been successful in East Asia’s high income economies, but culling is not the sole means to achieving the end of eliminating a pandemic threat. For example, in 1997, Hong Kong’s poultry culling schemes successfully led to an averted flu pandemic. In 2003, Japan and South Korea eradicated H5N1 through quarantine and poultry culling strategies, combined improved biosecurity measures for poultry facilities. After seeing the East Asian culling successes, the WHO was supportive of implementing poultry culling in Southeast Asia, “strongly recommending” its practice. Inspired by their neighbours and encouraged by the WHO, Southeast Asian countries began using poultry culling as a widespread H5N1 management and control technique. Unfortunately, it yielded different results. In Thailand, for example, culling resulted in only a temporary respite; after nearly a year of no H5N1 activity, new cases in humans were discovered in July 2006. What did work in Thailand, however, was a very different approach: effective risk communication particularly to rural communities, a comprehensive early detection system, passive and active surveillance, and strong partnerships with the US Centers for Disease Control in order to obtain laboratory technology and training, heightening reaction time in the event of an outbreak.

Ultimately, in examining the best way to respond to a pandemic outbreak, it remains essential to consider the specific circumstances of the country in which the outbreak occurred including its level of socioeconomic developments, and its geographical and climate peculiarities. The response to any pandemic outbreak should be tailored to the nature and pathology of the virus in question and not the contingency plan in place or the perceived appropriate political response.